Racket frame

ABSTRACT

A racket frame has a head frame, a triangular neck, and a handle. The head frame is oval-shaped and has a bottom end, and an arc opening defined at the bottom end of the head frame. The triangular neck is attached to the bottom end of the head frame and has a bridge and two arms. The bridge is made of fiber carbon composite and received inside the arc opening of the head frame. The two arms respectively attach to two distal ends of the bridge and further extend to abut the head frame. The handle is made of carbon composite and attaches to the triangular neck. By selectively using carbon fiber composite at the bridge and the handle, weight of the racket frame is minimized, durability of the racket is high and material cost of the racket frame is acceptable.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a racket frame, and more particularly to a tennis racket frame that is composed of different materials at different portions to make the racket durable, light and vibration-damping and have low manufacturing cost.

2. Description of Related Art

With reference to FIG. 9, a conventional racket frame is composed of a head frame (50), a forked neck (52), and a handle (54). The head frame (50) is oval-shaped and has a bottom end (not numbered) and an inner space (not numbered) in which a racket string (502) is woven. The forked neck (52) integrally extends from the bottom end of the head frame (50). Precisely, the forked neck (52) has two arms (not numbered) respectively extending downward from a 5-o'clock position and a 7 o'clock position on the head frame (50) according to clock orientation. The two arms extend downward and combine together to become a distal end. The handle (54) is attached to the distal end to achieve the racket frame.

Normally, the racket frame is made of carbon fiber composite or aluminum alloy tube, especially at the head frame (50) and the forked neck (52) integral with the head frame (50). However, the racket frame made of aluminum alloy tube has poor strength, bad vibration-damping efficiency and high weight in comparison with the one made of carbon fiber composite. With regard to the racket frame made of carbon fiber composite, although the racket frame has better physical properties than those of a racket frame made of aluminum alloy tube, the carbon fiber composite is expensive and so the material cost is much higher than the aluminum alloy tube.

The present invention has arisen to mitigate or obviate the disadvantages of the conventional racket frame.

SUMMARY OF THE INVENTION

The main objective of the present invention is to provide a racket frame that has different materials at different portions to make the racket frame have excellent physical properties.

To achieve the above-mentioned objective, the racket frame in accordance with the present invention comprises a head frame, a triangular neck, and a handle.

The head frame is oval-shaped and has a bottom end and two arc ends that define an arc opening defined at the bottom end of the head frame.

The triangular neck is attached to the bottom end of the head frame and comprises:

A bridge made of fiber carbon composite, engaging the head frame at the arc opening and having two distal ends and two side braces respectively formed at the two distal ends; and

-   -   two arms respectively having an abutting end attached to a         corresponding one of the two side braces of the bridge and a         free end extending to the handle.

The handle is preferably made of carbon fiber composite and attaches to the free ends of the two arms on the triangular neck.

By selectively using carbon fiber composite at the bridge and the handle, weight of the racket frame is low and durability of the racket is high. Additionally, because only certain parts of the racket frame are made of expensive carbon fiber composite and other parts can be made of less expensive materials, material cost of the racket frame is acceptable.

Further benefits and advantages of the present invention will become apparent after a careful reading of the detailed description with appropriate references to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a partially cross-sectional side view of a racket frame in accordance with the present invention;

FIG. 2-1 is an enlarged cross-sectional side view in partial section of a joint between a head frame and a triangular neck on the racket frame in FIG. 1;

FIG. 2-2 is an enlarged cross-sectional side view in partial section of a joint between the triangular neck and a handle on the racket frame in FIG. 1;

FIG. 3 is a cross-sectional side view of the joint between the head frame and the triangular neck along line A-A in FIG. 2-1;

FIG. 4 is a cross-sectional side view of the head frame along line B-B in FIG. 1;

FIGS. 5-1 to 5-4 are cross-sectional side views of four embodiments of an arm in the triangular neck along line C-C in FIG. 1;

FIG. 6 is a cross-sectional side view of the handle on the racket frame along line D-D in FIG. 1;

FIG. 7 is a partially cross-sectional side view of another embodiment of the racket frame in accordance with the present invention;

FIGS. 8-1 to 8-4 are cross-sectional side views of four embodiments of the handle of the embodiment along line E-E in FIG. 7; and

FIG. 9 is a partially cross-sectional side view of a conventional racket frame in accordance with the prior art.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

A racket frame in accordance with the present invention comprises a head frame, a triangular neck, and a handle. Wherein, the head frame is oval-shaped and has a bottom end, an arc opening defined at the bottom end of the head frame, and two arc ends formed on the head frame to define the arc opening. The triangular neck is attached to the bottom end of the head frame and comprises: a bridge made of carbon fiber composite and received inside the arc opening of the head frame and having two distal ends and two side braces respectively formed at the two distal ends, and two arms respectively having an abutting end attached to a corresponding one of the two distal ends of the bridge and a free end extending to the handle. The handle is preferably made of carbon composite and attaches to the two free ends respectively of the two arms on the triangular neck. Particularly, the head frame (1), the triangular neck (2) and the handle (3) are made of at least two different materials selecting from the carbon fiber composite, aluminum alloy, plastic, wood etc. wherein the carbon fiber composite and aluminum alloy are the preferred materials used in the present invention in following embodiments.

By selectively using carbon fiber composite at the bridge and the handle, the weight of the racket frame is low and the durability of the racket is high, along with the material cost of the racket frame being suitable for the market. With reference to FIGS. 1 and 2-1, a preferred embodiment of the racket frame comprises a head frame (1), a triangular neck (2), and a handle (3).

The head frame (1) is oval-shaped and has a bottom end, an arc opening defined at the bottom end of the head frame, and two arc ends (12) at the arc opening. With further reference to FIG. 4, the cross section of head frame (1) is a substantially oval tube with two longitudinal opposed curved side walls and two opposed curved end walls. An inward bend (102) is formed in one of the side walls The head frame (1) is selectively made of carbon fiber composite tube or aluminum alloy tube according to different designs of the racket frame. The two arc ends (12) define a length of the arc opening at the head frame (1) and are preferably and respectively at a 5 o'clock position and a 7 o'clock position in comparison with clock orientation.

The triangular neck (2) is attached to the bottom end of the head frame (1) and comprises a bridge (22) and two arms (21). The bridge (22) is shaped to complete the arc opening and is received between the arc ends. The bridge (22) has two tips and two side braces (222) respectively formed at the two tips. Each side brace (222) has an upper end (221) wedging into a corresponding one of the arc ends (12) to complete the head frame (1) and a lower end (223) to engage with a corresponding one of the arms (21). A cross-sectional side view of a joint of the upper end (211) and the arc end (12) of the head frame (1) is shown in FIG. 3, wherein the two ends (211, 12) are sleeved with each other. The side brace (222) is shaped to smoothly join with the head frame (1) and the two arms (21). The bridge (22) is particularly made of carbon fiber composite to dampen impact transmitted here.

The two arms (21) are made of aluminum alloy tube and respectively have an abutting end attached to a corresponding lower end (223) on the side brace (222) of the bridge (22). As shown in FIG. 2-1, the lower end (223) of the side brace (222) is wedged into the corresponding arm (21). Selectively, the arms (21) can be shaped into tubes having different cross-sectional shapes such as oval, rectangular, oval with two acute corners, or oval with two side cuts shown in FIGS. 5-1 to 5-4.

When the side braces (222) are to be combined with the head frame (1) and the arms (21), glue is applied at the joints for combination, or two adjacent elements are thermally set in a mold to firmly wedge with each other at the joints.

The handle (3) is preferably made of carbon fiber composite and has a cross-sectional view as shown in FIG. 6, which is hollow to achieve a light-weight racket frame. With reference to FIG. 2-2, the handle (3) has a forked end (32) with two upper connecting tubes respectively sleeving the lower ends (223) of the side braces (222) of the bridge (22). Means of combining the forked end (32) of the handle (3) and the arms (21) of the triangular neck (2) is also to use glue or to thermally set the elements in a mold.

When the racket frame is manufactured, pieces of carbon fiber composite (such as the bridge (22) and the handle (3)) are previously made by molding and all are hardened. Then, the head frame (1), the two arms (21), the bridge (22) and the handle (3) are coated with glue on their abutting surfaces and combined together to achieve the racket frame.

Selectively, the pieces of carbon fiber composite (such as the bridge (22) and the handle (3)) are previously made by rolling molding but without thermal setting. Then, the head frame (1), the two arms (21), the bridge (22), and the handle (3) are placed into a mold and thermally pressed to set the carbon fiber composite. Thereby, the pieces of carbon fiber composite expand slightly to firmly abut the ends on adjacent elements of the racket frame.

With reference to FIG. 7, another preferred embodiment of the racket frame in accordance with the present invention has the elements similar to the described one except the handle (3) and the arms (21) are in one-piece and integrally made of aluminum tubes. Therefore, the handle (3) is composed of two tubes and a plastic casing (31) surrounding around the two tubes. The plastic case (31) is preferably made of polyurethane forming material as used in most conventional racket frames, therefore, redundant description about the plastic case (31) is obviated here. In FIGS. 8-1 to 8-4, the handle (3) has multiple variations corresponding to the arms (21) shown in FIGS. 5-1 to 5-4.

By selectively using carbon fiber composite at the bridge and the handle, weight of the racket frame is low, durability of the racket is high, and impact vibration is interrupted and greatly reduced at the bridge and the handle. Additionally, because only certain parts of the racket frame are made of expensive carbon fiber composite, the material cost of the racket frame is acceptable.

Although the invention has been explained in relation to its preferred embodiments, many other possible modifications and variations can be made without departing from the spirit and scope of the invention as hereinafter claimed. 

1. A racket frame comprising: a head frame being oval-shaped and having a bottom end and two arc ends to define an arc opening at the bottom end of the head frame; a triangular neck attached to the bottom end of the head frame and comprising a bridge made of fiber carbon composite, received inside the arc opening of the head frame and having two distal ends and two side braces respectively formed at the two distal ends of the bridge two arms respectively having an abutting end attached to a corresponding one of the two side braces of the bridge and a free end; a handle attached to the two arms of the triangular neck; wherein, the head frame, the. arms of the triangular neck and the handle are respectively made of at least two materials selected from the group consisting of fiber carbon composite, aluminum alloy, plastic, and wood.
 2. The racket frame as claimed in claim 1, wherein the handle is made of carbon fiber composite.
 3. The racket frame as claimed in claim 1, wherein the two arc ends of the head frame define a length of the arc opening at the head frame and are preferably and respectively at a 5 o'clock position and a 7 o'clock position in comparison with clock orientation.
 4. The racket frame as claimed in claim 1, wherein each of the two side braces has an upper end wedging into a corresponding one of the two arc ends to complete the head frame; and a lower end wedging into the abutting end on a corresponding one of the arms.
 5. The racket frame as claimed in claim 2, wherein the two arms are made of aluminum alloy tubes.
 6. (canceled)
 7. The racket frame as claimed in claim 5, wherein the head frame is made of aluminum alloy tube.
 8. The racket frame as claimed in claim 1, wherein the handle and the arms are integrally made of two aluminum alloy tubes; and the handle further has a plastic casing surrounding the two aluminum alloy tubes.
 9. The racket frame as claimed in claim 1, wherein the racket frame is combined by gluing.
 10. The racket frame as claimed in claim 1, wherein the racket frame is combined by thermal setting in a mold. 